In recent years, gas turbines have been found to be an exceptionally useful engine in a variety of fields. Gas turbines are complex machines with extensive operation and maintenance requirements. Traditionally, gas turbine operation is defined by fixed schedules of operating parameters specified, for example, to reduce pollutants or produce a certain amount of power.
The pursuit of increased gas turbine efficiency requires gas turbines to be operated at a lean fuel-to-air ratio. Gas turbines operating on a lean fuel-to-air ratio generally produce undesired combustion pressure oscillations that may damage or reduce the lifespan of various gas turbine components.
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